Portable air conditioning apparatus



PORTABLE AIR CONDITIONING AI PARATUS File d March 16, 1954 Patented Nov. 24, 1936 UNITED STATES PATENT OFFICE Application March 16, 1934, .Serial No. 715,807. In Germany March 16, 1933 6 Claims.

This invention relates to portable air-conditioning apparatus, for cleansing the air of smoke, soot, germs, etc., while simultaneously heating, cooling, moistening or drying the cleansed air, as desired, before delivery to an enclosed space.

Many formsof apparatus for humidifying and cleansing or purifying air have already been described in publications from time to time, in which a motor-driven centrifugal pump (for example, a hollow inverted cone) dips at its lower end into washing liquid contained in a reservoir and, after raising liquid to its upper end, distributes it over a screen through or over which air to be treated is drawn by a fan which is co-axial with the pump and is driven by the pump motor, whereby the air is washed and cleansed or purified by the liquid. The said screen has consisted of a fabric or absorbent material, or perforated or expanded metal or gauze, which has been saturated or covered with the washing liquid supplied thereto by the pump, while air was drawn over or through the saturated or liquid-covered material or perforated metal or the like. So far as I am aware, such apparatuses have never been put into practice, and my gre- -searches show the probable reason for this, in that these apparatuses are practicallyinefiective to cool. the air, and thereby reduce its humidity, to any appreciable extent, and contice, particularly in tropical and sub-tropical countries. I have found that the chief reason why such former apparatuses have never been practically successful is that the screens provided, by means of which the air passing through the apparatus is treated, are wholly inadequate for presenting a practically effective heat-ex- .changing surface in contact with the air.

Hitherto, eflective air-conditioning, and in particular, air cooling and reduction of humidity, have only been obtainable by means of. large stationary plants. The principal object of my invention is to provide a portable apparatus of simple and compact construction, which, while being of small size and convenient to handle, is capable of efficiently and effectively conditioning, L and, in particular, cooling and reducing the humidity of, the air of relatively large enclosures, as satisfactorilyas the large stationary plants which have normally been employed hitherto.

As a result of considerable research and experiments I have found that a successful solution to the problem of producing a small portable air-conditioning apparatus which will satisfy practical requirements and function eflisequently they have never found favour in pracciently can be obtained when the following two conditions are fulfilled:

v 1. The washing liquid for treating the air must be brought into contact therewith, not in drop form, but as a film of considerable surface area. 5

2. A copious supply of liquid must be circu- -lated so that the quantity of liquid brought into contact with the air to be treated must substantially exceed the quantity of liquid required for evaporation by exchange of heat with the air 10 current. By employing such a copious stream of liquid the important advantage is obtained that while the temperature of the air is reduced by a substantial amount, the temperature of the circulating liquid is increased only to a relatively 15 small extent.

. My invention therefore consists in the combinations and arrangements of parts forming the improved portable air-conditioning, and in particular, air-cooling apparatus, all as hereinafter described and more particularly defined in the appended claims.

For a clear understanding of the invention, some constructional forms thereof are illustrated by way of example in the accompanying drawing forming part of my specification. In the drawing: I

Fig. 1 schematically represents in elevation, partly in section, one form of portable conditioning apparatus embodying the invention adapted to be supported, in the enclosureito be conditioned, on a standard, or a table, or a wall'bracket, and 4 c Fig. 2 schematically represents in elevation, partly in section, a further form of apparatus, for use on trains or other movable objects.

Fig. 1 shows an apparatus according to the invention employing a centrifugal fan and a centrifugal pump which is based on the well-known physical phenomenon of the fluid paraboloid. 40 The casing a of sheet iron, brass, copper or tl.-e like contains lower and upper liquid reservoirs e and f respectively. The air of the enclosure to be treated is aspirated through the filter g of large aggregate surface area by means of the centrlf- 5 ugal fan b, driven by the electric motor 0 and is expelled again into the enclosure at high speed with a swirling motion, so that the'radius of action, that is, the radius of the circular surface embraced by the effective air treatment amounts to at least 10 m. By arranging the air inlet and outlet openings concentrically as illustrated in Fig. 1, the effect is obtained that the induction and exhaust zones of the apparatus approximately constitute concentric bodies of rotation which do not interpenetrate and, therefore, also do not interact. As the arrows shown in Fig. 1 indicate, the induction zone in this case is a hemisphere of small diameter, but the exhaust zone is a cylinder of small height and large diameter. By means of this arrangement, therefore, a large enclosure volume is so uniformly treated that practically no temperature and moisture differences are at all existent and no draughts created. If, at the exit, certain directions are to be favoured and others disfavoured, the annular exit opening is partly covered by segments of slotted sliders or the like.

By providing a box-shaped collecting member on the air inlet side, it is possible to select the air to be conditioned from any preferred direction.

The centrifugal pump d comprises a hollow rotary conical body, provided with an opening at the bottom, with radially positioned interior metal sheets and a plurality of openings or discharge pipes at the upper end. The whole device is rigidly connected to the motor shaft and, on rotation, sets the liquid column in the interior into rotation, so that, owing to the centrifugal action, it climbs up the periphery and is hurled through the pressure openings or discharge pipes into the upper liquid container I.

From there, the liquid is distributed over the filter a, thoroughly saturating its surfaces and thereby covering them with a film of liquid of considerable aggregate surface area. The pump d is of such capacity as to discharge on to the filter a substantially more liquidthan is required for absorbing heat from the incoming air current, so that surplus liquid which is not evaporated by the exchange of heat with the incoming air current runs off from the bottom of the filter g and returns to the reservoir e. In order to separate from the air current any surplusmoisture accompanying it after its passage over the surfaces of the filter a, baflles of any suitable form are provided between the centrifugal pump d and the 'current, or a heater may be immersed in the washing liquid. For increasing the cooling effect, and thereby, the drying of the air, the washing liquid may be cooled directly by means of ice, or indirectly by means of a cooling coil provided in the apparatus. The removal of odours, particularly the pyrites compounds of tobacco smoke, is effected by the admixture of suitable salts, particularly iron chloride, to the washing liquid, and the removal of germs by ozonizing the air. The ozone is produced in well-known manner and mixed with the air before entering the apparatus. An increase in the effect of the ozone can be effected by mixing oxygen-evolving salts with the washing liquid. Ice added in summer for cooling purposes may preferably contain the said salts in solution.

The liquid reservoir e is provided with suitable means known per se for filling, emptying, preheating, ozonizing etc., as may be required for particular working conditions. Such devices are not specially illustrated in the drawing. ,However, an arrangement for cooling isspecially illustrated in this figure by the pipe coil is incorporated in the liquid reservoir e, the ends of this coil being led out of the reservoir. 7 The available refrigerant, such as spring water, cooled fresh thereby absorbs the heat of the washing liquid.

Fig. 2 shows an apparatus for vehicles, such as railway carriages, omnibuses, ships or the like,

tus intended for these uses is more limited in view of the necessity for having the opening in the deck, roof or the like. Instead of the wind motor with a fan, a simple ship's ventilator or the like may be employed. In all vehicles, external air is preferably aspirated and supplied, after conditioning, to the enclosure, whereby at the same time an excess pressure is produced in the enclosure, which itself is capable of preventing inconvenience due to dust and draughts. If the same ventilation and conditioning is to be obtained also when the vehicle is stationary, there is provided for the fan a second driving device, such as an electric motor, which is independent of the wind. As shown the filter 9 having a large aggregate surface area, consists of filling bodies packed in a hollow cylindrical perforated container. A screw-propeller pump it which is driven by the fan shaft and which runs in a hollow cylinder dipping below the surface of the liquid, raises the liquid and simultaneously distributes it through an annular slot at the upper end onto the filling bodies g. Arrows in the figure indicate the direction of the air current through the apparatus. If necessary, baiiies for separating the surplus moisture from the treated air current may be provided behind the filter. In Figure 2 a heating arrangement is shown in the form of a helical pipe coil l.- The heating medium may be hot water, steam, or electric current, and is immaterial for the purpose of the invention, but I arrange the heating surface in the liquid-moistened air space so as to obtain the following special effect. If heating without simultaneous moistening is to take place, the. ap-

paratus is operated without a water filling, that is, in dry condition, the air flows past the heating apparatus at high speed and is thereby heated. If, however, simultaneous moistening is desired, the heating surface is completely moistened by the washing liquid trickling down, so that the transfer of heat from the heating surface to the liquid takes place.

While I have described certain specific forms of apparatus for a clear understanding of my invention, I do not wish to be limited to these forms precisely, since some changes in constructional details and the combination and arrangement of the parts are possible within the scope of my invention as defined in and by the appended claims. For instance, with the hollow container packed with filling bodies, I may employ any combination of the fan and pump, apart from the particular combination illustrated. However, I prefer the combination of the centrifugal fan with the hollow cone centrifugal pump.

I claim:

1. Portable air-conditioning, and in particular, air cooling, apparatus, comprising the combina- 1 tion of a casing arranged with its axis vertically,

provided at its bottom with a liquid reservoir, and having air inlet and outlet openings; a motordriven fan within said casing positioned for moving a current of air through said casing from said inlet to said outlet, said inlet and outlet being positioned such that the induction zone, adjacent said inlet, from which air is drawn into said casing and the exhaust zone, adjacent said outlet, into which air is expelled from said casing do not interpenetrate; a hollow perforated container packed with filling bodies having a large aggregate surface area, so positioned that all the air driven through the apparatus by said fan must pass through said container and come into contact with the surfaces of said filling bodies; a centrifugal pump, driven by the fan motor and arranged co-axially with said fan, for raising liquid from said reservoir and discharging it onto said filling bodies, the arrangement of said container and said pump being such that all the liquid delivered by said pump from said reservoir is discharged onto said filling boiiies in said container and descends over their surfaces to thereby form liquid films of large aggregate surface area, said pump being adapted to irrigate said filling bodies with a quantity of liquid substantially in excess of that required for evaporation by exchange of heat with the incoming air current; said pump, container and casing being arranged concentrically, with said pump innermost.

2. The combination of a portable air-condition- I ing apparatus according to claim 1, with a heating device provided within the apparatus in the path of the air current.

3. Portable air-conditioning apparatus according to claim 1, in which the said pump comprises the combination of a vertically-arranged hollow cylinder having at its top end discharge ports or passages for liquid, and having its bottom end disposed within said reservoir, with a screw propeller within and at the bottom of said cylinder, within said reservoir, and connected to a shaft driven by the said fan motor, said propellerand cylinder being arranged coaxially with the said fan. I

4. Portable air-conditioning, and, in particular air cooling, apparatus for vehicles, comprising the combination of a casing arranged with its axis vertically, provided at its bottom with a liquid reservoir, and having an air inlet arranged at one side of its top end and in a substantially vertical plane and adapted to be located outside the enclosure to be conditioned, and having an air outlet in its side adapted to discharge air into said enclosure; a fan in the upper part of said casing near said inlet; means outside the top of said casing adapted to be driven by the wind, for driving said fan; a hollow perforated container packed with filling bodies having a large aggregate surface area, so positioned that all the air driven through the apparatus must pass through said container and come into contact with the surfaces of the said filling bodies; a centrifugal pump, driven by the fan motor, for raising liquid from said reservoir and discharging it onto'said filling bodies, the arrangement of said container and said pump being such that all the liquid delivered by said pump from said reservoir is discharged onto said filling bodies in said container, said pump being adapted to irrigate said bodies with a quantity. of liquid substantially in excess of that required for evaporation by exchange of heat with the incoming current; said pump, container and casing being arranged concentrically, with said pump innermost.

5. Portable air-conditioning apparatus according to claim 1, in which said inlet and outlet are so positioned that said induction and exhaust zones are coaxial with said casing.

6. Portable air-conditioning, and, in particular, air cooling, apparatus, comprising the combination of a casing arranged with its axis vertically, provided at its bottom with a liquid reservoir, and having an air inlet and an air outlet; a motor-driven fan within said casing positioned for moving a current of air through said. casing from said inlet to said outlet, said inlet and outlet being positioned such that. the induction zone, adjacent said inlet, from which air is drawn into said casing and the exhaust zone, adjacent said outlet, into which air is expelled from said casing do not interpenetrate; a filter having a large ag egate surface area so positioned that all the air moved through said casing by said fan must pass through said filter and come into contact with the surfaces thereofi a pump, driven by the fan motor and arranged co-axially with said fan, for raising liquid from said reservoir and discharging it on to said filter, the arrangement of said filter and said pump being such that all the liquid delivered by said pump from said reservoir is discharged on to said filter and descends .over its surfaces to thereby form liquid films of large aggregate surface area, said pump being adapted to irrigate said filter with -a quantity of liquid substantially in excess of that required for evaporation by exchange of heat with the incoming air current; said pump, filter and casing being arranged concentrically, with said pump innermost.

MAX BERLOWITZ. 

